I seem to remember a huge thread on POEN back in yon olden days where it was discussed the question "What bumper sticker would probably get your ass kicked the fastest?" and one of the top picks was "Dale Earnhardt Sucks Cocks In Hell."
The force exerted was equivalent to a vertical drop from a height of 61.8 foot (18.8 m). Subsequent sled testing of an exemplar vehicle yielded g-forces ranging from -68 g to -48.
It noted, among other things, that Earnhardt sustained:
Basilar skull fracture (fatal)
Eight broken ribs on his left side
Broken left ankle
Fractured sternum (possibly from attempted CPR)
Collarbone and hip abrasions (proving that the seat belts performed as designed)